Chapter 1: Energy
Lesson 1: Potential energy Lesson overview AQA Specification reference AQA 4.1.1.1, 4.1.1.2
Learning objectives • Consider what happens when a spring is stretched. • Describe what is meant by gravitational potential energy. • Calculate the energy stored by an object raised above ground level. Learning outcomes • Describe different types of energy store, including elastic potential energy and gravitational potential energy. [O1]
• Calculate, using the elastic potential energy equation. [O2] • Calculate, using the gravitational potential energy equation. [O3] Skills development • Evaluate methods and suggest possible improvements and further investigations. • Carry out and represent mathematical and statistical analysis. • Use SI units (for example, grams, metres, joules) and IUPAC chemical nomenclature unless inappropriate. Maths focus • Change the subject of an equation. • Substitute numerical values into algebraic equations using appropriate units for physical quantities. • Solve simple algebraic equations. Resources needed clamp stands, clamps, bosses, springs of known spring constant, 100 g mass holders, 100 g masses, metre rules, clear sticky tape, card, scissors; Worksheets 1.1.1, 1.1.2, 1.1.3, Practical sheet 1.1, Technician’s notes 1.1 Digital resources elastic potential energy video, gravitational potential energy video Key vocabulary energy store, energy transfer, elastic potential energy, gravitational potential energy, gravitational field strength
Teaching and learning Engage • Watch the elastic potential energy video showing archers shooting arrows. Challenge students’ thinking and understanding of the energy involved. You could ask: What energy does the arrow have when moving? Where does this energy come from? What type of energy does the bow have when the bowstring is pulled back? How can the energy be increased? Why would different bows contain different amounts of energy?
• Lead a discussion on the energy being stored in the bow until released by the archer – all stored energies are 2
called potential energies. Then introduce the equation for elastic potential energy: Ee = ½ ke . Formula triangles are trickier when there are more than three quantities, but show that it is possible with Ee at the top. 2 Emphasise that to determine e, students should use the triangle to find e , then take the square root. Note: students will always be given this equation in examinations on the physics equation sheet. [O1, O2]
• Watch the gravitational potential energy video showing pole-vaulters. Challenge students’ thinking and understanding of the energy involved. You could ask: What energy does the pole-vaulter have at the top of motion? Where does this energy come from? What type of energy does the pole have when it is bent? How would this be different for a heavier athlete? How would this be different on different planets?
AQA GCSE Physics: Teacher Pack
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